I guess the biggest benefit of regularly talking to people you have not talked to before is the reminder that there are other perspectives as well. Yours may be the best one. Or the right one. Or the one and only that fits the situation. But yours is not the only one.
I have worked with people from all walks of life. But by far the best were those who could ask questions that would rock my world. And the worst were those who never listened. But I guess they never had to because they were always right.